From d7d75352890447b55c13a81df316a6894ff32ecf Mon Sep 17 00:00:00 2001 From: Jaegeuk Kim Date: Mon, 11 Apr 2016 15:10:11 -0700 Subject: [PATCH 1/4] fscrypto: use dget_parent() in fscrypt_d_revalidate() This patch updates fscrypto along with the below ext4 crypto change. Fixes: 3d43bcfef5f0 ("ext4 crypto: use dget_parent() in ext4_d_revalidate()") Cc: Theodore Ts'o Signed-off-by: Jaegeuk Kim --- fs/crypto/crypto.c | 11 ++++++++--- 1 file changed, 8 insertions(+), 3 deletions(-) diff --git a/fs/crypto/crypto.c b/fs/crypto/crypto.c index 7f5804537d30..58ae0ba91ca2 100644 --- a/fs/crypto/crypto.c +++ b/fs/crypto/crypto.c @@ -345,13 +345,17 @@ EXPORT_SYMBOL(fscrypt_zeroout_range); */ static int fscrypt_d_revalidate(struct dentry *dentry, unsigned int flags) { - struct inode *dir = d_inode(dentry->d_parent); - struct fscrypt_info *ci = dir->i_crypt_info; + struct dentry *dir; + struct fscrypt_info *ci; int dir_has_key, cached_with_key; - if (!dir->i_sb->s_cop->is_encrypted(dir)) + dir = dget_parent(dentry); + if (!d_inode(dir)->i_sb->s_cop->is_encrypted(d_inode(dir))) { + dput(dir); return 0; + } + ci = d_inode(dir)->i_crypt_info; if (ci && ci->ci_keyring_key && (ci->ci_keyring_key->flags & ((1 << KEY_FLAG_INVALIDATED) | (1 << KEY_FLAG_REVOKED) | @@ -363,6 +367,7 @@ static int fscrypt_d_revalidate(struct dentry *dentry, unsigned int flags) cached_with_key = dentry->d_flags & DCACHE_ENCRYPTED_WITH_KEY; spin_unlock(&dentry->d_lock); dir_has_key = (ci != NULL); + dput(dir); /* * If the dentry was cached without the key, and it is a From 33b1395124c63ed4a42e33c1dd14859f9b3f29c2 Mon Sep 17 00:00:00 2001 From: Jaegeuk Kim Date: Mon, 11 Apr 2016 15:15:38 -0700 Subject: [PATCH 2/4] f2fs: use dget_parent and file_dentry in f2fs_file_open This patch synced with the below two ext4 crypto fixes together. In 4.6-rc1, f2fs newly introduced accessing f_path.dentry which crashes overlayfs. To fix, now we need to use file_dentry() to access that field. Fixes: c0a37d487884 ("ext4: use file_dentry()") Fixes: 9dd78d8c9a7b ("ext4: use dget_parent() in ext4_file_open()") Cc: Miklos Szeredi Cc: Theodore Ts'o Signed-off-by: Jaegeuk Kim --- fs/f2fs/file.c | 10 +++++++--- 1 file changed, 7 insertions(+), 3 deletions(-) diff --git a/fs/f2fs/file.c b/fs/f2fs/file.c index 443e07705c2a..90d1157a09f9 100644 --- a/fs/f2fs/file.c +++ b/fs/f2fs/file.c @@ -441,7 +441,7 @@ static int f2fs_file_mmap(struct file *file, struct vm_area_struct *vma) static int f2fs_file_open(struct inode *inode, struct file *filp) { int ret = generic_file_open(inode, filp); - struct inode *dir = filp->f_path.dentry->d_parent->d_inode; + struct dentry *dir; if (!ret && f2fs_encrypted_inode(inode)) { ret = fscrypt_get_encryption_info(inode); @@ -450,9 +450,13 @@ static int f2fs_file_open(struct inode *inode, struct file *filp) if (!fscrypt_has_encryption_key(inode)) return -ENOKEY; } - if (f2fs_encrypted_inode(dir) && - !fscrypt_has_permitted_context(dir, inode)) + dir = dget_parent(file_dentry(filp)); + if (f2fs_encrypted_inode(d_inode(dir)) && + !fscrypt_has_permitted_context(d_inode(dir), inode)) { + dput(dir); return -EPERM; + } + dput(dir); return ret; } From b32e4482aadfd1322357f46d4ed8a990603664d9 Mon Sep 17 00:00:00 2001 From: Jaegeuk Kim Date: Mon, 11 Apr 2016 15:51:57 -0700 Subject: [PATCH 3/4] fscrypto: don't let data integrity writebacks fail with ENOMEM This patch fixes the issue introduced by the ext4 crypto fix in a same manner. For F2FS, however, we flush the pending IOs and wait for a while to acquire free memory. Fixes: c9af28fdd4492 ("ext4 crypto: don't let data integrity writebacks fail with ENOMEM") Cc: Theodore Ts'o Signed-off-by: Jaegeuk Kim --- fs/crypto/crypto.c | 36 ++++++++++++++++++++---------------- fs/f2fs/data.c | 16 +++++++++++++--- include/linux/fscrypto.h | 9 +++++---- 3 files changed, 38 insertions(+), 23 deletions(-) diff --git a/fs/crypto/crypto.c b/fs/crypto/crypto.c index 58ae0ba91ca2..da70520f3ab4 100644 --- a/fs/crypto/crypto.c +++ b/fs/crypto/crypto.c @@ -81,13 +81,14 @@ EXPORT_SYMBOL(fscrypt_release_ctx); /** * fscrypt_get_ctx() - Gets an encryption context * @inode: The inode for which we are doing the crypto + * @gfp_flags: The gfp flag for memory allocation * * Allocates and initializes an encryption context. * * Return: An allocated and initialized encryption context on success; error * value or NULL otherwise. */ -struct fscrypt_ctx *fscrypt_get_ctx(struct inode *inode) +struct fscrypt_ctx *fscrypt_get_ctx(struct inode *inode, gfp_t gfp_flags) { struct fscrypt_ctx *ctx = NULL; struct fscrypt_info *ci = inode->i_crypt_info; @@ -113,7 +114,7 @@ struct fscrypt_ctx *fscrypt_get_ctx(struct inode *inode) list_del(&ctx->free_list); spin_unlock_irqrestore(&fscrypt_ctx_lock, flags); if (!ctx) { - ctx = kmem_cache_zalloc(fscrypt_ctx_cachep, GFP_NOFS); + ctx = kmem_cache_zalloc(fscrypt_ctx_cachep, gfp_flags); if (!ctx) return ERR_PTR(-ENOMEM); ctx->flags |= FS_CTX_REQUIRES_FREE_ENCRYPT_FL; @@ -147,7 +148,8 @@ typedef enum { static int do_page_crypto(struct inode *inode, fscrypt_direction_t rw, pgoff_t index, - struct page *src_page, struct page *dest_page) + struct page *src_page, struct page *dest_page, + gfp_t gfp_flags) { u8 xts_tweak[FS_XTS_TWEAK_SIZE]; struct skcipher_request *req = NULL; @@ -157,7 +159,7 @@ static int do_page_crypto(struct inode *inode, struct crypto_skcipher *tfm = ci->ci_ctfm; int res = 0; - req = skcipher_request_alloc(tfm, GFP_NOFS); + req = skcipher_request_alloc(tfm, gfp_flags); if (!req) { printk_ratelimited(KERN_ERR "%s: crypto_request_alloc() failed\n", @@ -199,10 +201,9 @@ static int do_page_crypto(struct inode *inode, return 0; } -static struct page *alloc_bounce_page(struct fscrypt_ctx *ctx) +static struct page *alloc_bounce_page(struct fscrypt_ctx *ctx, gfp_t gfp_flags) { - ctx->w.bounce_page = mempool_alloc(fscrypt_bounce_page_pool, - GFP_NOWAIT); + ctx->w.bounce_page = mempool_alloc(fscrypt_bounce_page_pool, gfp_flags); if (ctx->w.bounce_page == NULL) return ERR_PTR(-ENOMEM); ctx->flags |= FS_WRITE_PATH_FL; @@ -213,6 +214,7 @@ static struct page *alloc_bounce_page(struct fscrypt_ctx *ctx) * fscypt_encrypt_page() - Encrypts a page * @inode: The inode for which the encryption should take place * @plaintext_page: The page to encrypt. Must be locked. + * @gfp_flags: The gfp flag for memory allocation * * Allocates a ciphertext page and encrypts plaintext_page into it using the ctx * encryption context. @@ -225,7 +227,7 @@ static struct page *alloc_bounce_page(struct fscrypt_ctx *ctx) * error value or NULL. */ struct page *fscrypt_encrypt_page(struct inode *inode, - struct page *plaintext_page) + struct page *plaintext_page, gfp_t gfp_flags) { struct fscrypt_ctx *ctx; struct page *ciphertext_page = NULL; @@ -233,18 +235,19 @@ struct page *fscrypt_encrypt_page(struct inode *inode, BUG_ON(!PageLocked(plaintext_page)); - ctx = fscrypt_get_ctx(inode); + ctx = fscrypt_get_ctx(inode, gfp_flags); if (IS_ERR(ctx)) return (struct page *)ctx; /* The encryption operation will require a bounce page. */ - ciphertext_page = alloc_bounce_page(ctx); + ciphertext_page = alloc_bounce_page(ctx, gfp_flags); if (IS_ERR(ciphertext_page)) goto errout; ctx->w.control_page = plaintext_page; err = do_page_crypto(inode, FS_ENCRYPT, plaintext_page->index, - plaintext_page, ciphertext_page); + plaintext_page, ciphertext_page, + gfp_flags); if (err) { ciphertext_page = ERR_PTR(err); goto errout; @@ -275,7 +278,7 @@ int fscrypt_decrypt_page(struct page *page) BUG_ON(!PageLocked(page)); return do_page_crypto(page->mapping->host, - FS_DECRYPT, page->index, page, page); + FS_DECRYPT, page->index, page, page, GFP_NOFS); } EXPORT_SYMBOL(fscrypt_decrypt_page); @@ -289,11 +292,11 @@ int fscrypt_zeroout_range(struct inode *inode, pgoff_t lblk, BUG_ON(inode->i_sb->s_blocksize != PAGE_SIZE); - ctx = fscrypt_get_ctx(inode); + ctx = fscrypt_get_ctx(inode, GFP_NOFS); if (IS_ERR(ctx)) return PTR_ERR(ctx); - ciphertext_page = alloc_bounce_page(ctx); + ciphertext_page = alloc_bounce_page(ctx, GFP_NOWAIT); if (IS_ERR(ciphertext_page)) { err = PTR_ERR(ciphertext_page); goto errout; @@ -301,11 +304,12 @@ int fscrypt_zeroout_range(struct inode *inode, pgoff_t lblk, while (len--) { err = do_page_crypto(inode, FS_ENCRYPT, lblk, - ZERO_PAGE(0), ciphertext_page); + ZERO_PAGE(0), ciphertext_page, + GFP_NOFS); if (err) goto errout; - bio = bio_alloc(GFP_KERNEL, 1); + bio = bio_alloc(GFP_NOWAIT, 1); if (!bio) { err = -ENOMEM; goto errout; diff --git a/fs/f2fs/data.c b/fs/f2fs/data.c index 53fec0872e60..5dafb9cef12e 100644 --- a/fs/f2fs/data.c +++ b/fs/f2fs/data.c @@ -992,7 +992,7 @@ submit_and_realloc: if (f2fs_encrypted_inode(inode) && S_ISREG(inode->i_mode)) { - ctx = fscrypt_get_ctx(inode); + ctx = fscrypt_get_ctx(inode, GFP_NOFS); if (IS_ERR(ctx)) goto set_error_page; @@ -1092,14 +1092,24 @@ int do_write_data_page(struct f2fs_io_info *fio) } if (f2fs_encrypted_inode(inode) && S_ISREG(inode->i_mode)) { + gfp_t gfp_flags = GFP_NOFS; /* wait for GCed encrypted page writeback */ f2fs_wait_on_encrypted_page_writeback(F2FS_I_SB(inode), fio->old_blkaddr); - - fio->encrypted_page = fscrypt_encrypt_page(inode, fio->page); +retry_encrypt: + fio->encrypted_page = fscrypt_encrypt_page(inode, fio->page, + gfp_flags); if (IS_ERR(fio->encrypted_page)) { err = PTR_ERR(fio->encrypted_page); + if (err == -ENOMEM) { + /* flush pending ios and wait for a while */ + f2fs_flush_merged_bios(F2FS_I_SB(inode)); + congestion_wait(BLK_RW_ASYNC, HZ/50); + gfp_flags |= __GFP_NOFAIL; + err = 0; + goto retry_encrypt; + } goto out_writepage; } } diff --git a/include/linux/fscrypto.h b/include/linux/fscrypto.h index cd91f75de49b..6027f6bbb061 100644 --- a/include/linux/fscrypto.h +++ b/include/linux/fscrypto.h @@ -263,9 +263,9 @@ static inline void fscrypt_set_d_op(struct dentry *dentry) extern struct kmem_cache *fscrypt_info_cachep; int fscrypt_initialize(void); -extern struct fscrypt_ctx *fscrypt_get_ctx(struct inode *); +extern struct fscrypt_ctx *fscrypt_get_ctx(struct inode *, gfp_t); extern void fscrypt_release_ctx(struct fscrypt_ctx *); -extern struct page *fscrypt_encrypt_page(struct inode *, struct page *); +extern struct page *fscrypt_encrypt_page(struct inode *, struct page *, gfp_t); extern int fscrypt_decrypt_page(struct page *); extern void fscrypt_decrypt_bio_pages(struct fscrypt_ctx *, struct bio *); extern void fscrypt_pullback_bio_page(struct page **, bool); @@ -299,7 +299,8 @@ extern int fscrypt_fname_usr_to_disk(struct inode *, const struct qstr *, #endif /* crypto.c */ -static inline struct fscrypt_ctx *fscrypt_notsupp_get_ctx(struct inode *i) +static inline struct fscrypt_ctx *fscrypt_notsupp_get_ctx(struct inode *i, + gfp_t f) { return ERR_PTR(-EOPNOTSUPP); } @@ -310,7 +311,7 @@ static inline void fscrypt_notsupp_release_ctx(struct fscrypt_ctx *c) } static inline struct page *fscrypt_notsupp_encrypt_page(struct inode *i, - struct page *p) + struct page *p, gfp_t f) { return ERR_PTR(-EOPNOTSUPP); } From 03a8bb0e53d9562276045bdfcf2b5de2e4cff5a1 Mon Sep 17 00:00:00 2001 From: Jaegeuk Kim Date: Tue, 12 Apr 2016 16:05:36 -0700 Subject: [PATCH 4/4] ext4/fscrypto: avoid RCU lookup in d_revalidate As Al pointed, d_revalidate should return RCU lookup before using d_inode. This was originally introduced by: commit 34286d666230 ("fs: rcu-walk aware d_revalidate method"). Reported-by: Al Viro Signed-off-by: Jaegeuk Kim Cc: Theodore Ts'o Cc: stable --- fs/crypto/crypto.c | 4 ++++ fs/ext4/crypto.c | 4 ++++ 2 files changed, 8 insertions(+) diff --git a/fs/crypto/crypto.c b/fs/crypto/crypto.c index da70520f3ab4..2fc8c43ce531 100644 --- a/fs/crypto/crypto.c +++ b/fs/crypto/crypto.c @@ -26,6 +26,7 @@ #include #include #include +#include #include #include @@ -353,6 +354,9 @@ static int fscrypt_d_revalidate(struct dentry *dentry, unsigned int flags) struct fscrypt_info *ci; int dir_has_key, cached_with_key; + if (flags & LOOKUP_RCU) + return -ECHILD; + dir = dget_parent(dentry); if (!d_inode(dir)->i_sb->s_cop->is_encrypted(d_inode(dir))) { dput(dir); diff --git a/fs/ext4/crypto.c b/fs/ext4/crypto.c index db9ae6e18154..6a6c27373b54 100644 --- a/fs/ext4/crypto.c +++ b/fs/ext4/crypto.c @@ -32,6 +32,7 @@ #include #include #include +#include #include "ext4_extents.h" #include "xattr.h" @@ -482,6 +483,9 @@ static int ext4_d_revalidate(struct dentry *dentry, unsigned int flags) struct ext4_crypt_info *ci; int dir_has_key, cached_with_key; + if (flags & LOOKUP_RCU) + return -ECHILD; + dir = dget_parent(dentry); if (!ext4_encrypted_inode(d_inode(dir))) { dput(dir);